1. Field of the Invention
The invention, in general, relates to an apparatus for the scanning of working levels and, more particularly, to an apparatus for scanning the working level between a cutting tool and a cutting surface in water jet cutting machines and laser cutting machines for the prevention of damage to tools as may otherwise result from collision.
2. The Prior Art
Apparatus manually adjustable and controllable by an operator and provided with sensors for scanning working levels are known. They do, however, suffer from such drawbacks as requiring extreme attention on the part of the operator and their sensors being easily be damaged by a reflected water jet or by abrasion. Such apparatus are generally incapable of detecting very small surface irregularities such as burrs, scales, dripping residues or rust, so that there is always a high risk of damage to their cutting tools.
German Utility Model U1 299 05 304.0 discloses a pneumatic device for water jet and laser cutting machines which seeks to avoid collisions between the cutting tool and surface irregularities in the cutting material by dynamically scanning the surface.
One disadvantage of such devices is that at the occurrence of a mechanical overload as may be caused by a collision of the tool, the sluggishness of the pneumatic drive and the slow rate at which such devices process measured values, they offer no reliable protection from damage to the cutting tool. Since neither the speed of response of such devices nor stroke and surface pressure of the scanning arm can be set or programmed by an operator, damage to costly sensitive material as a result of scratches is rather likely.
It is a general object of the invention to provide an electro-mechanical apparatus for scanning the working level of water jet and laser cutting devices.
A more specific object of the invention resides in the provision of an apparatus for scanning the working level of a water jet or laser cutting machine whose scanning arm surface pressure on the material to be cut may be programmed.
Yet another object of the invention is to provide an apparatus for scanning the working level of a water jet or laser cutting machine which is provided with collision protection means of adjustable sensitivity or responsiveness.
Still another object of the invention resides in the provision of a scanning apparatus of the kind referred to which prevents mechanical overloads of the cutting device.
In the accomplishment of these and other objects, the present invention, in a preferred embodiment thereof, provides an apparatus for scanning the working level of a water jet or laser cutting tool provided with a scanning arm which is movable into its operating position by a linear motor and the surface pressure of which is electrically or mechanically adjustable and controllable throughout its entire stroke, in dependency of the material to be treated. Alternatively, the scanning arm may be programmed to any position along its stroke.
Preferably, the linear motor unit including a linear slide and linear guide rod of the scanning arm as well the scanning arm mounted on the linear guide rod are mounted for substantially omnidirectional pivotal movement by a flexible mount and/or ball joint seated in a cantilever, the linear motor unit being maintained in a stable neutral position by at least one spring arranged between the linear motor unit and the cantilever.
A collision switch structured as a well known inductive proximity switch may be actuated by a link connected to the linear motor unit.
The link is movably connected to the linear motor unit and may be pivotally and slidingly moved in a fulcrum in a support, support and fulcrum being mounted on a spindle and may be adjusted relative thereto for changing the transmission ratio of the lever arrangement.
Other objects and advantages will in part be obvious and will in part appear hereinafter.